9 & 15 THE ESPLANADE
Perth, Australia
CLIENT Brookfield Properties
PROGRAM Two mixed-use towers on Elizabeth Quay, including Class A offices, a 4-star boutique hotel, luxury residences, and an elevated “Plus” of amenities; street-level retail and food & beverage; and below-grade parking
AREA 9 The Esplanade: 45,300 m2 (488,000 sf); 15 The Esplanade: 105,000 m2 (1,130,000 sf)
SUSTAINABILITY 6 Star ‘Green Star,’ NABERS Energy 5.5 Star, Gold WELL
COST 9 The Esplanade: US$155 million; 15 The Esplanade: US$565 million
STATUS Invited competition, first prize 2016; 9 The Esplanade completed 2025; 15 The Esplanade completed Schematic Design 2021
DESIGN ARCHITECT REX
PERSONNEL Elias Arkin, Julie Bauer, Wanjiao Chen, Adam Chizmar (PL), Maur Dessauvage, Nazle Ergani, Alvaro Fernandez Gomez-Selles, Kelvin Ho, Sebastian Hofmeister, Young Kang, Nicolas Lee, Kirby Liu, Weronika Marciniak, Isabelle Moutaud, Elizabeth Nichols, Joshua Ramus, Raúl Rodríguez García, Emma Silverblatt, Alfonso Simelio Jurado, Elina Chizmar (PL), Anne Strüwing (PL), Vaidotas Vaiciulis, Cristina Webb (PL), Xuancheng Zhu
EXECUTIVE ARCHITECTS Hassell, REX (enclosure)
CONSULTANTS Arup, Cermak Peterka Petersen, Front, Fytogreen, JMG Building Surveyors, Magnusson Klemencic, Patrick Blanc, PTS Town Planning
CONTRACTOR Multiplex
The client’s objectives for 9 & 15 The Esplanade seem at odds: a building pair that must be an urban landmark, yet meet the rigor of speculative development and be responsive to significant market fluctuations during a lengthy design process. The design capitalizes on this dichotomy and rethinks conventional attitudes toward property development. It begins by eschewing the typical signature-status strategy that gives primacy to the building form, regardless of its impact on commercial plan dimensions and its inflexibility to programmatic change.
For example, even the simple, truncated-pyramid geometry of the John Hancock Center (with residences at its top and offices at its base) yields only a few plans with optimal window-to-core dimensions, while all others become increasingly unfavorable for layout. In that approach, the signature form becomes a geometric straightjacket.
Instead, 9 & 15 The Esplanade comprises four elements (three ideally dimensioned commercial program blocks and one highly unique “Plus” of amenities) whose composition establishes a clear design direction and aesthetic coherence, while allowing for significant programmatic modulation throughout the design process.
By keeping the commercial program blocks discrete, their dimensions and the resulting pro forma can be parametrically adjusted like a stereo equalizer, …
… limited only by the slenderness ratio of the taller tower’s core and the elevator speeds necessary to service its Class A offices. Market exposure is thus reduced to only three months—the period between submitting the exterior envelope for wind tunnel analysis and starting foundation construction based on those results—rather than years of a form-driven design process.
The cantilevered dynamic Plus of amenities inserted between 15 The Esplanade’s two commercial blocks becomes a beacon visible from around the city, …
Hanging garden within the central galleria
… frees additional retail space at the tower’s base, …
By isolating the project’s unique program within the Plus, difficulties associated with these complex programs—such as circulation, egress, and security—are also contained. As a result, the creation of construction documents for the rest of the building can accelerate, with construction commencing over a year before the Plus design is complete.
Each of the Plus’s four arms houses a distinct amenity: meeting rooms, a restaurant, a gym, and a ballroom. They each have their own architectural expression, dramatically revealed at night.
By keeping each amenity independent, their architectural characteristics can be easily redefined during design, and—by using lightweight, sustainable construction materials—adaptively changed over the building’s life.
Taking its cue from other new mixed-use developments with high-occupancy “elevated islands,” the Plus is reached via four high-speed, double-decker shuttle elevators that efficiently service these loads.
The elevated Plus also expedites construction, with the following sequence:
- The below-grade retention system is erected from grade with slurry walls. Deep bored pile foundations are installed, and below-grade excavation is completed.
- Construction of the tower’s concrete core begins with a “climbing form” system ahead of the floor slabs. While the core is hiking up, the MEP level––consisting of structural steel trusses (the “Launch Pad”)––is assembled around it at grade.
- Strand jacks are placed around the core above the first hotel level and are calibrated to lift the Launch Pad into place. Simultaneously, the Plus’s mega truss and floor truss framing are assembled on grade.
- Conventional concrete construction of the hotel levels commences, utilizing flat plate, post-tensioned slabs, and concrete columns. The Plus trusses are lifted into place with strand jacks.
- Construction of the hotel and residential levels continues. Simultaneously, construction of the office levels begins from grade, using concrete wide-shallow beams and slabs or composite structural steel framing.
Compared to conventional concrete core-and-slab buildings, this sequencing reduces construction by two to four months, allowing the critical path of the hotel and residential blocks to advance in the schedule.
The façade is composed of a unitized aluminum curtain wall with structural silicone, achieving a flush exterior, expressed behind an overlay of structural mullions. The mullions are relocated outboard of the façade to increase usable area, improve aesthetics (by creating a thinner frame on the building’s interior), perform as shading fins, and enhance the building’s external beauty.
The office floor façade units are 1.5 m x 4 m, and 1.4 m x 3.4 m for the hotel and residential floors. These sizes allow for competitive bidding, a wide range of procurement options, and straightforward curtain wall installation.
Mock-up
The panels are factory-unitized into a four-sided frame and hung from the buildings’ floor slabs, like a conventional curtain wall. The aluminum fins are connected to one side of the curtain wall unit, and the adjacent panel braces the other side, allowing the façade to accommodate building movements while maintaining narrow profiles to maximize sight lines.
Image credits: 1, 2, 8, 11, 13, 14, 15, 16 © Luxigon; 3 © Ricky Esquivel; all others © REX